When an album sells a million copies, it gets certified as platinum and cements itself as one of its generation's biggest hits. When an album sells 10 million copies, it reaches diamond status and transcends generational gaps. But when an album sells well over 40 million copies, there's only one thing you can call it—Michael Jackson's Thriller.

That's right, MJ has the highest-selling album of all time, and second place isn't even close. And now, thanks to an awesome offer from Google Play Music, you can add to those astronomical sales numbers by grabbing a copy without even paying a dime. As if that weren't enough of a deal already, they're even including a rare home demo version of "Billie Jean" with this release, so you'd be crazy to pass this one up.

'Buying' Your Free Copy of Thriller

This week only, Thriller is absolutely free—but you'll still need a credit card to process the $0.00 "transaction," and you'll need to be in the U.S. to take advantage of the offer, or mask your location via VPN. Considering it's being offered by Google Play Music, you'll of course need a Google account as well—then if you'd like to listen to the album on your smartphone, you'll have to download the Google Play Music app for Android or iOS.

But with the fine print out of the way, all you really need to do is head to the link below to get your free copy of Thriller.

Of course, the album was produced by Quincy Jones before he moved on to television projects like Fresh Prince, and it features guest appearances by legends such as Sir Paul McCartney and Eddie Van Halen. But the highlight of this particular release is a home demo version of "Billie Jean," which was recorded in 1981 partially as a pitch to the album's producers, and is included as a 10th track at the end of the album.

What's your favorite track from Thriller? I have to go with "Billie Jean" myself, but I'm sure "Beat It" and the title track are at the top of a lot of lists. Either way, be sure to give us your opinions in the comment section below.